I recently cooked the pump in my spare LU, and my original one is down also. So after checking the merc part numbers between my orig (327xxxx 1972 115hp) and sierra part numbers and kits. I ordered LU seal kit 18-2655, and complete pump kit 18-3314. When I opened the package and compared the parts to my originals, everything seems good except the pump base. It has no flush hole, and one extra vent groove? on the impeller side neat the front bolt hole. This groove is next to the small groove that vents the driveshaft seal area, the the outside of the pump. It goes from the pressure(output) side of the impeller, to the outside of the pump. Any comments or advice? Can I use it without the flush port? Where do you guys get your parts for pre 469xxxx motors? Thanks in advance.
